# Step 5: Attach Part 500_12A

> Attach part 500_12A in the L-shaped groove on part 500_03C.

- Page: https://docs.menlo.ai/asimov/1/build/assembly-steps/right-leg-module/thigh-assembly/step-5
- Section: Asimov › Asimov 1 › Assemble Asimov 1 › Assemble › Right Leg Module › Thigh Assembly
- Previous: [Step 4: Attach Part 500_06A](https://docs.menlo.ai/asimov/1/build/assembly-steps/right-leg-module/thigh-assembly/step-4.md)
- Next: [Step 6: Install the Outer Housing](https://docs.menlo.ai/asimov/1/build/assembly-steps/right-leg-module/thigh-assembly/step-6.md)

> [!IMPORTANT]
> **Assign actuator IDs before assembly**
>
> Assign and verify all 25 actuator IDs before assembling the robot. The robot will not work correctly with missing or incorrect IDs. IDs must be assigned one actuator at a time on the bench; you may need to disassemble the robot if you skip this step. See [Assign Actuator IDs](https://docs.menlo.ai/asimov/1/build/assembly-preparations/assign-actuator-ids.md).

## Parts needed

| Part | Count |
| - | -: |
| Current assembly from Step 4 | 1 |
| `500_12A` | 1 |
| M3x6 Socket bolt | 2 |
| Threadlocker | As needed |

## Instructions

1. Turn the current assembly around such that the L-shape grove is facing upward toward the ceiling and toward you.

2. Take part `500_12A` and align it with the L-shape grove on part `500_03C`.

3. Take **2 of** M3x6 Socket bolts and lightly tighten them into the 2 holes on part `500_12A` to align it with part `500_03C`.

4. After the parts are aligned:

   > [!NOTE]
   >
   > **Not ready to apply threadlocker?**
   >
   > You can assemble without threadlocker while you check the fit, alignment, and orientation. When you are confident, disassemble as needed, apply threadlocker to the bolts, and reassemble them following these instructions.

   - remove **2 of** M3x6 Socket bolts one at a time,
   - apply threadlocker,
   - then tighten them back to secure Part `500_12A` and part `500_03C` together.